There has been known the following technique. A through-hole is formed on a cushion member disposed at a seat back of a vehicle seat. A cover member made of a resin material covers an inner peripheral surface of the through-hole. For example, Patent Literature 1 discloses a vehicle seat that includes a functional element 1 (a cover member) including a tubular body 10 and a flange 11. The functional element 1 is engaged with a through-hole 30 formed at a pad 3 (a cushion member).
However, the above-described conventional technique covers an opening of the through-hole 30 at a rear side of a seat back SB by a skin material 6 (a skin). Accordingly, the through-hole 30 cannot communicate between a front side and the rear side of the seat back SB.